The problems associated with separating or treating complex streams of substances in order to enrich the various valuable substances contained therein arise particularly in the field of biogenically-based aqueous liquids, such as, for example, liquids from fermentation processes and in particular liquids obtained from silage.
Liquids obtained from whole-plant silage or silage from grassland biomass (such as, e.g., from grass, clover, alfalfa, herbs etc.) have for some time been regarded as interesting raw materials for the obtainment of fine chemicals. In the following, the term “grass silage” is used to represent all silages from grassland biomass.
In the context of the “Österreichisches Programm zur Entwicklung der Green Biorefinery [Austrian Programme for the Development of Green Biorefinery]” it has been shown that valuable substances accumulating during the silage process of, e.g., grass, such as lactic acid and proteinogenic amino acids, convert the biogenic raw material grass into a potentially interesting source for obtaining such valuable substances. This concept is interesting particularly because of the possibility of using an inexpensive and, in addition, renewable raw material.
It is, however, problematic that the complex streams of substances accumulating, for example, with the grass silage comprise a plurality of valuable substances of a varying chemical nature the separation of which is difficult.